land_ownership · spacing
Spacing/Drilling Unit Acres
Spacing Unit Acres = Base Section Acres × Aliquot Fraction (or Section Multiple)
click formula to derive ↑
Inputs
acres
fraction
Description
Computes the total acreage of a pooled spacing or drilling unit from the base section acreage and the unit's size relative to one section — merging what would otherwise be two near-identical calculators (a fixed acres-per-section lookup and a general acres-per-spacing-unit conversion), since both reduce to the identical acreage = 640 × fraction/multiple computation. Feeds directly into Royalty Interest's 'Spacing Unit Acres' input.
Variables
| Symbol | Unit | Description |
|---|---|---|
| A_u | acres | Spacing Unit Acres |
| A_s | acres | Nominal acreage of one full PLSS section — 640 acres in the standard U.S. Public Land Survey System; edit only if the governing survey uses a non-standard section size. |
| f | fraction | Size of the pooled spacing or drilling unit relative to one full section — a PLSS aliquot fraction (e.g. 0.25 for a quarter section, 0.0625 for a quarter-quarter/40-acre tract) for a sub-section unit, or a whole-number multiple (e.g. 2 for a 1,280-acre two-section horizontal spacing unit) for a multi-section unit, per the governing pooling/spacing order. |
Assumptions
- The unit is a single contiguous spacing/drilling unit of the stated fraction or multiple of one section — irregular or non-rectangular units (e.g., unit exceptions, oversized units from a tolerance allowance) must have their actual surveyed acreage entered directly rather than derived from a nominal fraction.
- Base Section Acres reflects the actual governing survey system; PLSS states default to 640, but metes-and-bounds states (e.g., Texas) may require entering the tract's actual surveyed acreage as 'Base Section Acres' with a unit_fraction of 1.
Limitations
- Nominal PLSS acreage can differ slightly from actual surveyed acreage (resurveys, government lot adjustments) — use the acreage stated in the governing spacing/pooling order or survey where precision matters.
- Does not itself determine which fraction or multiple applies to a specific well — that is set by the state regulatory agency's spacing/pooling order for the applicable field and formation, not derived here.
Use Cases
- → Pre-pooling unit sizing: Determine a spacing unit's total acreage from its aliquot-part or multi-section description before computing tract participation in Royalty Interest.
- → Pooling order verification: Confirm a pooling order's stated unit acreage against the aliquot fraction or section multiple it describes.
Related Calculations
Region Notes
General (U.S. PLSS states)
Common sub-section spacing unit sizes are 640 (full section), 320 (half), 160 (quarter), 80 (half-quarter), and 40 acres (quarter-quarter) — always confirm the actual unit size and fraction from the governing spacing or pooling order.
Oklahoma
Oklahoma has increased its maximum horizontal spacing unit size from 640 acres to 1,280 acres, permitting two-section (and other multiunit) horizontal spacing configurations — confirm the applicable maximum and actual unit size from the OCC spacing order for the specific field and formation.
Texas and other metes-and-bounds states
Non-PLSS states describe tracts by metes and bounds rather than section aliquot fractions — surveyed acreage can be any value, not a simple fraction of 640; enter the tract's actual surveyed acreage as Base Section Acres with a Unit Fraction of 1.
References
Need geoscience support? BauerCalc is just one of the tools we build. If you're looking for independent expertise in well planning, geosteering, reservoir characterization, or opportunity evaluation, visit BauerSubsurface.com.